Foes in Ambush by Charles King

A riot in Chicago is subdued with the use of the US Cavalry, and someone falls in love in the process. This is a fast-moving tale of a riot, the Cavalry, and romance. Not to be missed. This is a weird tale. It's a bit fanciful, because the US Cavalry has never been used to quell a riot, unless this observer is mistaken. Any thoughts on that?